A high speed page width ink jet printer has recently been developed by the present applicant. This typically employs in the order of 51,200 ink jet nozzles to print on A4 sheet paper to provide photographic quality image printing at 1,600 dpi. In order to achieve the nozzle density, the nozzles are fabricated by integrating MEMS-CMOS technology and this context reference may be made to International Patent Application No. PCT/AU00/00338 lodged by the present Applicant and entitled “Thermal Actuator”.
These high speed page width ink jet printers produce an image on a sheet by causing an actuator arm to move relative to a substrate by forming the actuating arm in part from an electrically resistive material and by applying a current to the arm to effect movement of the arm. The arm is connected to a paddle so that upon movement of the arm the paddle is moved to eject a droplet of ink onto the sheet. In order to eject the droplet ink the paddle extends into a nozzle chamber which has a nozzle aperture and movement of the paddle causes the droplet to be ejected from the nozzle aperture.